1. Field of the Invention
The present invention relates to a heat sink assembly, and particularly to a heat sink assembly having a fixing device for readily and firmly attaching a fan to a heat sink.
2. The Related Art
Many electronic devices, such as Central Processing Units (CPUs), generate large amounts of heat during operation. This frequently deteriorates the operating stability of the electronic devices. Typically, a heat sink assembly with a fan is used to dissipate heat generated by an electronic device.
Referring to FIG. 5, a conventional heat sink assembly as disclosed in Taiwan Patent Application No. 86206427 includes a heat sink 70, a fan 50 and a fixing device 60 which attaches the fan 50 to the heat sink 70. The fan 50 is secured on the fixing device 60 with screws. Two arms 62 extend downwardly from opposite sides of the fixing device 60. Each arm 62 forms a catch 622. The fan 50 is attached to the heat sink 70 by the catches 622 engaging with apertures 72 defined in the heat sink 70.
However, securing the fan 50 to the fixing device 60 with screws is cumbersome and time-consuming. Furthermore, the fixing device 60 is attached to the heat sink 70 by means of just two catches 622 engaging with two apertures 72. This leaves the assembly prone to dislodgement when subjected to shock or vibration during normal operation.
An improved means of securing a fan to a heat sink, which overcomes the above problems, is desired.
Accordingly, an object of the present invention is to provide a heat sink assembly having a fixing device which firmly and reliably attaches a fan to a heat sink.
Another object of the present invention is to provide a heat sink assembly which is readily assembled and disassembled.
To achieve the above-mentioned objects, a heat sink assembly in accordance with the present invention comprises a fan, a heat sink, and a fixing device which attaches the fan to the heat sink. The heat sink has a chassis and a plurality of fins extending upwardly from the chassis. Four catches are formed on respective outermost fins, two on each of two longitudinal sides of the heat sink. The fixing device has a base and four legs depending from respective corners of the base. Four poles extend upwardly from the base near respective corners of the base. A pair of protrusions depends from the base near respective opposite lateral sides of the base. Each leg defines an aperture for engaging with the corresponding catch of the heat sink. The fan defines four through holes for receiving the poles of the fixing device. The fan is thereby firmly securable to the heat sink.
Other objects, advantages and novel features of the present invention will be apparent from the following detailed description of preferred embodiments of the present invention with reference to the attached drawings, in which: